Not all diarrhea is the same. If diarrhea occurs abruptly and subsequently stretches over a few days, pathogens such as viruses or bacteria are usually responsible. Long-lasting, chronic diarrhea can be the cause of serious illnesses.

Possible causes of acute diarrhea:

• Gastrointestinal infections: mostly bacteria and viruses, such as noroviruses, rotaviruses or coliform bacteria (Escherichia coli) or salmonella. Caution: Gastrointestinal infections are highly contagious!
• Spoiled food can lead to food poisoning. The triggers here are bacteria that produce toxins.
  
• Food allergies or food intolerances: usually followed by a rapid reaction after eating certain foods. Possible causes can be: Histamine intolerance, lactose intolerance, gluten intolerance (celiac disease), allergies (e.g. to milk, nuts, fruit, protein or fish).
  
• Poisoning: usually caused by chemicals or fungi.
• Infectionswith parasites, such as amoeba or lamblia (giardiasis).
• Menstruation: Hormonal changes and the increased release of endogenous messenger substances such as prostaglandins are responsible for the fact that about one third of all women experience diarrhea during their menstruation – even if they do not normally have bowel problems.
• Medications: Antibiotics, cancer drugs (cytostatics), iron supplements, or dietary supplements (vitamin C) can cause diarrhea.
• Travel:Unfamiliar, highly spiced or very fatty foods can be a cause of traveler’s diarrhea – also known as Montezuma’s Revenge. In most cases, however, contact with contaminated food or water or bacteria previously unknown to the body is behind it.
• Anxiety or stress

Possible causes of chronic diarrhea are:

• Hyperthyroidism (overactive thyroid gland)
  
• Irritable Bowel Syndrome
  
• Tumor diseases
• Chronic inflammatory bowel diseases: Ulcerative colitis (chronic inflammation in the rectum and/or colon), Crohn’s disease (chronic inflammation that can affect the entire digestive tract).
  
• Chronic intestinal infectionscaused by viruses, bacteria or parasites
  
• Chronic inflammation of the gastric mucosa(chronic gastritis)
  
• Intestinal protrusions (diverticulosis) with inflammation (diverticulitis)
• Malassimilation syndrome (insufficient absorption and utilization of food components)